The present disclosure generally relates to the field of in vitro diagnostics and, in particular, to a system and method for automatically handling biological samples.
Clinical laboratories face the challenge of having to process an increasing number of sample tubes per day while still having to guarantee that the analytical results derived from the samples are reproducible and correct. Errors may arise both in the pre-analytical, analytical and post-analytical stage of a potentially highly complex sample processing workflow. An additional challenge is the fact that a huge variety of different sample types exist which further complicate the handling and automated processing of the samples. In one aspect, the diversity of the sample tubes results from the diversity of sample processing workflows and tests which have meanwhile been developed for various diagnostic, analytical or other purposes.
In another aspect, the diversity results from different sample manufacturers using different materials, sample tube dimensions and cap color codes for collecting and processing different kinds of biological samples (e.g. blood, urine, serum or plasma samples) and/or for different kinds of analytical tests (coagulation tests, clinical chemistry tests, hematological tests, etc.). To meet the requirements in respect to analysis quality and cost effectiveness, intelligent solutions in the field of automated sample-handling devices are required.
Current pre- and post-analytical systems as well as analyzers require information on tube geometry, sample type, target volumes, cap type etc. in order to correctly handle and process sample tubes. In current systems, this information is gathered by cameras and/or sensors, or is defined by a user manually. Any manually executed step is, however, error prone and time consuming and therefore not suitable for implementing a high-quality sample processing workflow. Image analysis based approaches are often time consuming and may be error-prone. Errors may occur when frozen or very cold samples comprising ice or condensation water on their surface need to be processed. Ice and water may change the shape and optical parameters of a sample tube and may cause errors when an image is taken from such a sample for image analysis. Errors may also be caused by tubes sitting not vertically but diagonally in the rack, by a too weak light source being inadequate for letting the camera reliably detect the color of the tube or of the tube cap or may be caused by the tube protruding from the tube rack or by other error sources.
Therefore, there is a need to provide for an improved method and system for sample tube and sample tube handling.